A saddle-ridden type vehicle such as a motorcycle is provided with a supercharger and air compressed by the supercharger is supplied to a combustion chamber of an engine, so that it is possible to increase a thermal efficiency and an output of the engine. Patent Document 1 discloses a saddle-ridden type vehicle having a supercharger.
The saddle-ridden type vehicle disclosed in Patent Document 1 has an air cleaner configured to purify exterior air, a supercharger configured to compress the air purified by the air cleaner, an intercooler configured to cool the air of which a temperature has increased resulting from the compression by the supercharger, and a surge tank configured to temporarily store therein the air cooled by the intercooler and to supply the same to an engine. Also, in the saddle-ridden type vehicle, the air cleaner and the supercharger are interconnected by an air intake piping. Also, the supercharger and the intercooler are interconnected by an air outlet piping. Also, the intercooler and the surge tank are disposed adjacent to each other and are directly interconnected via a short pipe line.
Patent Document 1: Japanese Patent Application Publication No. 2015-83437A
The saddle-ridden type vehicle configured to compress the air by the supercharger and to supply the same to the engine has more components of an intake system, as compared to natural intake, because the supercharger, the intercooler, the air outlet piping configured to interconnect the same, and the like are provided. Also, in the supercharger (turbocharger) configured to drive a turbine by using an exhaust gas of the engine, it is necessary to smoothly supply the exhaust gas to the turbine of the supercharger. Therefore, it is preferably to dispose the supercharger in the vicinity of an exhaust port provided at a front part of the engine. Due to this, the supercharger is disposed in front of the engine in many cases. On the other hand, since an intake port of the engine is provided at a rear part of the engine, the surge tank configuring a downstream-side of the intake system is disposed at the rear of the engine in many cases. Further, an arrangement place of the air cleaner is limited due to a relation with a layout of a path (a duct and the like) configured to guide the exterior air, which is to be used for combustion of fuel, to the air cleaner. Also, an arrangement place of the intercooler is limited due to a relation with a layout of a path configured to guide the exterior air, which is to be used for cooling of the compressed air, to the intercooler. Due to the situations, in the saddle-ridden type vehicle having the supercharger, it is difficult to determine positions around the engine, at which the plurality of components of the intake system is to be disposed.
In the saddle-ridden type vehicle of Patent Document 1, the air cleaner is disposed at a lower-rear side of the engine, the supercharger is disposed at a lower-front side of the engine, and the intercooler and the surge tank are disposed at the rear of the engine. Since the supercharger and the intercooler are dispersedly disposed at the front and rear of the engine and are distant from each other, the air outlet piping configured to interconnect the supercharger and the intercooler is long. For this reason, a resistance against the air flowing through the air outlet piping is large, so that a response of the engine to a throttle operation may decrease or a turbo lag may increase.
Also, in the saddle-ridden type vehicle of Patent Document 1, since the air intake piping and the air outlet piping configured to interconnect the air cleaner, the supercharger and the intercooler dispersedly disposed at the front and rear of the engine are disposed at a side of the engine, a vehicle width of the saddle-ridden type vehicle may increase.
In the saddle-ridden type vehicle of Patent Document 1, the air cleaner, the intercooler and the surge tank are separate components, the air cleaner is disposed at a lower-rear side of the engine, the intercooler is disposed at the rear of the engine, and the surge tank is disposed above the intercooler. Like this, in the saddle-ridden type vehicle of Patent Document 1, the components of an intake system such as the air cleaner, the intercooler and the surge tank are separate members and are dispersedly disposed around the engine. For this reason, when manufacturing the saddle-ridden type vehicle, the man-hour of mounting the components of the intake system to a vehicle body increases. Also, since mounting positions and directions of the respective components of the intake system are different, a mounting ability of the components is poor.
Also, since the components of the intake system are dispersedly disposed around the engine, the components protrude in a plurality of upper, lower, front, rear, right and left directions. For this reason, it is difficult to make the saddle-ridden type vehicle small. Also, since the components of the intake system are dispersedly disposed around the engine, pipings configured to interconnect the components are also dispersedly disposed around the engine and are lengthened. As a result, it is difficult to reduce a vehicle width of the saddle-ridden type vehicle.